Primary total hip arthroplasty in patients older than 90 years of age - a retrospective matched cohort study

Introduction: Advanced age is considered a major risk factor for postoperative complications in total hip arthroplasty (THA). Consequently, older patients undergoing THA may require more detailed pre-procedural examinations and more healthcare resources postoperatively than younger patients. The purpose of this study was to compare discharge parameters and complication rates of THA in patients > 90 years old to those Methods: A retrospective review of 14,824 THA patients from 2011 to 2021 at a high-volume, urban academic centre was conducted. Patients > 90 years old were propensity-matched to a control group of patients aged <90 years old. Patient demographics, surgical time, hospital length of stay (LOS), discharge disposition, and 90-day revision, readmission, and mortality rates were collected. Demographic differences and outcomes were assessed using chi-square and independent sample t-tests. Results: After propensity matching, the average age in the younger cohort (YC, n = 54) was 75.81 +/- 7.89, and 91.61 +/- 1.73 for the older cohort (OC, n = 54). The OC had a longer LOS than the YC (mean 3.90 vs. 3.06 days; p = 0.031). Discharge disposition significantly differed (p = 0.007); older patients were more likely to be discharged to skilled nursing facilities (33.3% vs. 14.8%) or acute rehabilitation centres (14.8% vs. 3.7%) and less likely to be discharged to prior place of residence (home self-managed/home with services, 51.9% vs. 79.6%). There was no significant difference in surgical time (93.87 +/- 29.75 vs. 96.09 +/- 26.31 min; p = 0.682), 90-day revision rate (3.7% vs. 0%; p = 0.153), 90-day readmission rate (9.4% vs. 3.7%; p = 0.543), and 90-day mortality rate (1.9% vs. 1.9%; p = 1.000). Conclusions: Although THA patients over 90 years of age had a longer LOS and differing discharge disposition, these patients had similar complications compared to their younger counterparts. Thus, our study supports similar efficacy of THA in patients 90 years and older relative to younger THA candidates.